Even when snow blankets South Dakota’s frozen ground and most farmers have wrapped up their season, Cedar Creek Gardens keeps growing. Nestled about 12 miles south of Interstate 90, near Murdo, this farm uses special hoop-shaped tunnels to keep vegetables thriving far beyond typical harvest times.
These farm tunnels are tall, plastic-covered structures that trap the sun’s heat, creating warm conditions inside—almost like a simple greenhouse. Unlike greenhouses, the crops at Cedar Creek grow right in the soil, watered from below instead of sprayed from above. Many tunnels here have two layers of plastic with warm air circulating between them, making the growing space even cosier.
The story of these tunnels goes back more than 20 years. Peggy Martin and Bud Manke, who run Cedar Creek, started using them after reading about the idea online. What began as a way to feed their families grew into a passion and an expanding business. Thanks to the tunnels, they extend their growing season by up to four months each year, even harvesting fresh produce as late as mid-December—months past South Dakota’s average first frost in mid-September.
Their farm spans 14 acres, dotted with about a dozen tunnels, some as tall as 14 feet and 200 feet long. They grow everything from giant kale and one-pound tomatoes to banana peppers, onions, pumpkins, melons, broccoli, and more. Alongside the vegetables, they raise about 1,400 free-range laying hens and cattle. Their products are sold at local markets and through wholesale channels serving grocery stores and restaurants in the region.
Cedar Creek’s approach isn’t just about growing longer; it’s about growing better. The tunnels protect crops from harsh weather like wind, hail, and frost, and help reduce water and pesticide use. Martin points out that their tomatoes produce more than double the fruit of typical plants. With three rows of 100 plants per tunnel, each plant making about 40 pounds of fruit, a single tunnel can yield over $21,000 worth of tomatoes in one season.
South Dakota’s Natural Resources Conservation Service supports this method through financial assistance programs. Rachel Lawton, who manages these efforts, says the tunnels work best for specialty crops rather than large-scale commodity farming. Each year, about a dozen tunnel projects receive funding to help with installation costs and conservation planning. But Lawton warns that tunnels need regular upkeep and careful management to avoid damage and overheating.
Martin has become something of an expert in the community, earning the title of the state’s “high tunnel resident expert.” She knows that these tunnels require constant attention—rolling down sides before storms and venting heat on hot days.
For farmers willing to put in the effort, the rewards can be big. Longer growing seasons, higher-quality produce, and a smaller environmental footprint all add up. It means more fresh food for the season and better profits for the farm.
In a state where winters are long and tough, the simple plastic tunnels at Cedar Creek Gardens are making a big difference. They help keep the farm growing, the farmers busy, and the local tables stocked with fresh, tasty vegetables well into the cold months.